Posted by & filed under Child Development, Cognitive Development: Piagetian and Vygotskian Approaches, Consciousness, Development of the Self, Health Psychology, Higher-Order Cognitive Functions in Aging, Human Development, Neuroscience, The Self.

Description: The age of majority is 18 where I live, 19 where I grew up and 21 in some other jurisdictions. This is the age at which one can drink legally, vote, and other things. It is also the age at which the local justice system starts to treat you as an adult and to hold you totally responsible for your actions and related decisions. Younger offenders (from 12 to 17 years of age in Canada) are viewed as young offenders and are subject to the Young Offenders Act. The purpose of the act, essentially, is to respond to young offenders in ways that reflect the belief that they are not yet fully developed and as such treated in ways that hold out the possibility that they will be better citizens with some intervention, support or further development. To assign them a criminal record would not take into account their remaining developmental potential. How do we know this? Well, we know it based on general observation and experience but not with nearly as much research data in support as you might think.  For example, are the brains of late teenagers fully developed? …in ways that matter for the mature self-management of their own behaviour? Well, the fact that most jurisdictions have graduated drivers’ licensing programs (get a provisional license and then gain 6 months to two years of on-road experience under conditions of limited access to road risk before getting your “real” license would suggest that we seem to know teenagers have a way to go developmentally. Does turning 18 mean that all young people are ready to be upstanding citizens and ready to be held fully culpable for ALL of their actions? What do you think? With your thoughts in mind read the article linked below to see both what neuroscience has to say about the notion of 18 as the age of maturity AND what some courts are undertaking in the way of alternative court processes and treatments for young adults on the basis of this neuroscience research.

Source: A California Court for Young Adults Calls on Science, Tim Requarth, Health, New York Times.

Date: April 17, 2017

Photo Credit:  Laura Morton for the New York Times

Links:  Article Link —

I have served as an expert witness for the crown over the past 2 years here in Alberta Canada. I was asked to speak to the question of what developmental research has to say about the potential harms associated with young people in their early to mid-teenage years (12 to 16) becoming involved sexually with individuals older than them (3 years older for 12 to 14 year olds and 5 years older for 14 to 16 year olds). Many jurisdictions have increased the age before which young people cannot be viewed as providing defensible consent to sexual activity (such laws used to be called statutory rape laws). One of the central factors supporting such laws are the findings noted in the linked article; that brain development is not complete by 16 or even by 18 or perhaps 20 to 22 years of age. At the same time that frontal lobe areas of the brain involved in self-regulation are developmentally under-functioning the reward monitoring centers of the brain are over-functioning. This leads to the consistently verified finding that young adults ARE capable of demonstrating advanced rational thinking in “cool” situations (think school logic problems) but when things warm up (in peer groups or when access to “adult” activities and interests are in play) the reward centers of the brain light up and the self-control areas cool down and do not often provide the level of self-control necessary for rational decision-making. 18 years of age is a rather arbitrary marker of “maturity” and developmental neuroscience is causing us to think harder of about when to offer young adults, adult-levels of license for their behaviour and when to them hold to adult levels of responsibility-related consequences for their actions. Young adult courts are providing opportunities for young adults to move forward from inappropriate or dangerous actions in ways that do not close a door on ongoing development or on future full participation in adult life.

Questions for Discussion:

  1. Should 18 year olds be held responsible for all of their actions in the same manner as adults?
  2. In what ways are the brains of late adolescents and young adults still developing?
  3. How is the ongoing development you discussed in response to the previous question related to the sorts of situations that may give rise to problematic behavioural opportunities for young adults? What should be done about young people in such situations?

References (Read Further):

San Francisco, Young Adult Court:

Giedd, J. N., Blumenthal, J., Jeffries, N. O., Castellanos, F. X., Liu, H., Zijdenbos, A., … & Rapoport, J. L. (1999). Brain development during childhood and adolescence: a longitudinal MRI study. Nature neuroscience, 2(10), 861-863.

ROPER V. SIMMONS (03-633) 543 U.S. 551 (2005)

Steinberg, L., Cauffman, E., Woolard, J., Graham, S., & Banich, M. (2009). Are adolescents less mature than adults?: Minors’ access to abortion, the juvenile death penalty, and the alleged APA” flip-flop.”. American Psychologist, 64(7), 583.

Thye MacArthur Foundation Research Network on Law and Neuroscience

Cohen, A. O., Breiner, K., Steinberg, L., Bonnie, R. J., Scott, E. S., Taylor-Thompson, K. A., … & Silverman, M. R. (2016). When is an adolescent an adult? Assessing cognitive control in emotional and nonemotional contexts. Psychological science, 0956797615627625.,%20Breiner,%20Steinberg,%20et%20al%20(2016)%20When%20is%20an%20adolescent%20an%20adult.pdf